


Spirit of Scientific Inquiry

by BlushingNewb



Category: Sherlock (TV)
Genre: Established Relationship, Johnlock Roulette, M/M, Oral Fixation, Plot What Plot/Porn Without Plot, Rimming, Shy Sherlock, references to switch!lock
Language: English
Status: Completed
Published: 2015-05-11
Updated: 2015-05-11
Packaged: 2018-03-30 00:25:53
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,783
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3916312
Author URL: https://archiveofourown.org/users/BlushingNewb/pseuds/BlushingNewb
Summary: <blockquote class="userstuff">
              <p>John has it in mind to add a certain set of activities to their sexual repertoire. Sherlock is still new to this whole physical intimacy thing and feels conflicted about his lover's proposal.</p>
            </blockquote>





	Spirit of Scientific Inquiry

**Author's Note:**

  * For [AtlinMerrick](https://archiveofourown.org/users/AtlinMerrick/gifts).



> This is a gift for the talented and amazing AtlinMerrick, who is wonderfully creative, thoughtful and kind -- you have been an inspiration to me. Thank you so much for everything.
> 
> Shout out also to DoubleNegative and Anarfea for their generosity in beating this fic with the beta stick. You're incredible, the pair of you.

"You want to do what?" an indignant Sherlock squawked, his voice rising in alarm. He jerked away from the warm lips mouthing at the space below his ear.

John ran soothing fingers through Sherlock's loosening curls, just beginning to dampen at the roots. Sherlock, not to be put off, tried to pull away but John tugged him back. Thinking quickly of how seldom his lover asked him to repeat himself, John attempted to clarify.

"Just putting it on the table, love. There's nothing we ever _have_ to do."

Sherlock narrowed his eyes in full deduction mode, but, relenting at something he saw in John's face, he finally relaxed back onto the mattress. Sherlock licked his lips, and for a moment, John saw what could almost be described as embarrassment flicker through his eyes.

"That... _it_...seems so unhygienic," Sherlock mumbled, clearly uncomfortable with restating John's inquiry. He looked away and John felt his heart turn over, the way he always did when he was reminded of how new this was for Sherlock, of how much trust this extraordinary man had given him.

"Um, yeah," John replied, "yeah, there's that, but that's really all down to preparation. And maybe this is the opposite of most people, but whenever I get...ready..." John's face heated. "It's just a reminder of what's going to..." He cleared his throat awkwardly. "Anyway. I just wanted to let you know how I felt, in case you were ever interested in it," John finished. He slid his fingers further into Sherlock's hair, rubbing fingertips over his scalp. Sherlock rumbled out a pleased noise and arched up into John's touch. He pressed up into his thigh, and John was delighted to note that Sherlock’s state of arousal was mostly undiminished.

* * *

Later, as they clung to one another, sweat-damp and sated, Sherlock watched the movement under John's eyelids as he slid into sleep. He mulled over the proposal and considered. This would require research, and although Sherlock was skeptical of the result, he had always enjoyed data-gathering.

* * *

Websites, ranging from the anonymously salacious to the dryly clinical, guaranteed that with the proper preparation there was little danger of transmitting E-coli or other diseases. Wriggling in his chair a bit, Sherlock thought over John's eagerness and an uncomfortable yet pleasurable feeling of utter filthiness washed over him. John was a doctor and he was willing to...ready to...

_What would it feel like?_

Sherlock pulled up half a dozen tabs of pornography, all directed toward a specific line of sexual activity. One tab was dismissed immediately. Boring. Two more were rejected once Sherlock deduced that the actors were straight. The third -- my god, Sherlock thought, why bother at all after the eggplant? Four and five...Sherlock's ears burned. Was that what John saw as he prepared him? Was that what he looked like? He felt mortified.

But Sherlock loved looking at John everywhere; _he_ was extraordinary. So pink, so responsive to his touch; he opened to his fingers and his cock in a way that -- Sherlock looked around the room surreptitiously and gave his prick a good hard rub. He clicked tabs four and five shut without another glance.

Now, tab six. Amateur. Sherlock squinted. The pair were very fond of one another, he concluded, perhaps even in love. A slender white man and a stockier man with dark skin twined around one another on a double bed with green sheets. They were exhibitionists, doing this for the thrill of it rather than for the small fee their website collected. The camera was set up in a stationary position a meter from the bed; there would be no extreme close-ups.

At the black man's behest, the other man stretched out upon the mattress. Sherlock focused on the expression on his face as his legs were parted and his partner buried his face in his arse. Two spots of red bloomed on Sherlock's cheeks as he watched the man's features contort in pleasure, watched his body jerk at the unseen movements his lover was making below. Sherlock sat motionless throughout the whole scene, stunned.

After clearing the browser history, Sherlock slammed the lid shut on the laptop. John wanted to do that to him. John. Was he hoping for reciprocation? John had obviously done it before, twice with a woman and then she had done it for him. Sherlock hated that this made him feel inadequate, when he knew that he was superior in every way to all of John's previous partners.

Well. Never let it be said that Sherlock Holmes did not have a spirit of scientific inquiry.

* * *

But before Sherlock could conduct further research, they got pulled into a case that left them both exhausted. It had been tedious at the start but picked up in the middle, culminating with a clumsy hostage situation resolved by a thoroughly fed-up John, who neatly dispatched the thief with the butt of his gun.

In the cab back to 221b, John drooled all over his own coat lapel while Sherlock watched him with heavy-lidded eyes. Mrs. Hudson had to pay for the take-away that arrived while they dozed in the living room, and a grousing John stuffed pork dumplings into Sherlock's mouth and his own. They lapsed into unconsciousness in their bed, half-dressed and nearly dead to the world.

* * *

It was eight in the evening of the next day, and they had lazed about the flat, napping, reading and watching telly. They were curled up on the sofa at present, and Sherlock had his arm around John, who had his legs splayed out in front of him. He was only wearing pants and a robe, and Sherlock found himself increasingly distracted from fussing at _Traffic Cops_ by the sight of John's naked thighs. They were strong and lovely, dusted with fine, golden hair, and Sherlock had many delicious memories of the way they tightened around him.

Some minutes later he came out of his reverie to find that he had been repeatedly massaging a patch of skin on John’s upper arm with his thumb. Sherlock ceased his movements, and, just as he had convinced himself that they had gone unnoticed, John turned to face him. It suddenly occurred to Sherlock that John was still far more of an adept at the science of seduction than he was and the thought of it made his toes curl.

With an exaggerated wink, John stretched out from underneath Sherlock's arm and made a slow grind into the air with his hips. When Sherlock inhaled a short, sharp breath at the sight, John slid to the floor and rubbed his lips over Sherlock's cock, still trapped in his pants and cotton pajama bottoms.

Sherlock swallowed hard and his nostrils flared. "Yes?" John asked. Sherlock nodded quickly and rubbed John's fingers with his own where they toyed with his waistband.

"Please," he let out in a strained voice. "It's been...it's been..." He left off when John licked a slow stripe over him, dampening the cotton fabric. "How long, Sherlock?" John asked, making sure that Sherlock could feel the movement of his mouth over his swelling prick. Sherlock minutely bucked his hips in frustration.

"Five days, nine hours, forty-three minutes. Give or take a few seconds," he gasped.

"Good man," John said, rolling Sherlock’s underwear and bottoms down to his ankles as he lifted his hips. Sherlock's cock bobbed up eagerly and John steadied him with a hand at the base, giving him small, firm strokes. Sherlock grunted and his fingers scrambled fruitlessly on the couch as hot breaths ghosted over him. He fought against the desperate urge to push John's head down onto him, grip his hair and fuck his mouth. Sherlock loved it when they took turns surrendering on their knees to one another until they both came out the victor. But it was obvious that John was in the mood to tease him. Rough would be for another time, and the anticipation of the delicious agony John was offering him now heated his blood.

John ran his tongue around the ridge of Sherlock's glans, stubbornly ignoring the wetness at his slit. "What do you want?" he asked, grinning up at him. Sherlock averted his eyes. Oh, John, so wicked, so clever. Making him voice his desires, when John knew it made him squirm.

"Please, John," he whispered, feeling his face flame, "suck me."

John lowered his mouth and took him in all the way, pushing his nose up against his pubis. Sherlock's eyes slammed shut at the sudden glorious sensation. _Hot mouth, so sweet. Slick tongue and wet, so good, good my John_. Sherlock knew vaguely that he was babbling some or all of these things when John rose most of the way up and encircled his cock with a fist. Then he started working Sherlock with his tongue, licking him, caressing him. John massaged his fraenulum with the flat of his tongue and kissed that sensitive spot with several gentle sucks before circling his tongue around the crown. But when John began humming in pleasure, sending tonal vibrations via his cock directly into his cerebral cortex, Sherlock's brain stuttered a bit. He felt like his prick was being worshipped by the most devout of followers and he opened his eyes wide in wonder.

John had his own eyes closed, dark gold lashes curled against his cheeks. Sherlock realized that if he could he'd be smiling in satisfaction, like the cat who'd got the cream. And what's more, John had pulled out his own cock at some point and was wanking himself with abandon. Sherlock watched a shudder go through John's body as his lips closed around Sherlock's cock again. John was incredibly aroused by this, was masturbating even as he gave Sherlock what had to be the most decadent blowjob in history.

John opened his eyes, and Sherlock felt caught in the maelstrom, roped in by the adoration he saw there. John's soft tongue licked up Sherlock's pre-cum right from the source, and as John took him completely in his mouth again, he pressed a knuckle up behind his balls. Sherlock jerked over John's tongue when he sucked him down hard and his mouth formed an 'O' as he arrived at a startling conclusion.

Doctor and soldier, thought Sherlock. A natural giver as a lover, but powerful, dominant in his generosity, revelling as he doled out pleasure. Especially when he could use his lips, his tongue, any part of his mouth to satisfy that oral fixation. The man licked his lips constantly, twisted them with every expression, pursed them in consternation and twitched them when he was about to laugh. Oh, shit. John loved giving this to Sherlock not because he expected anything back but because he _got off on it_.

I got it wrong, thought Sherlock. Wrong deduction, wrong deduct----

His orgasm caught him off guard and he spilled in John's mouth, his body battered by waves of endorphins as he envisioned John humping their bed, his tongue swiping over Sherlock's hole.

* * *

John, already close after tasting Sherlock fall apart, was pleasantly surprised when Sherlock skipped over his post-orgasmic haze to haul him up onto the sofa. Sherlock slathered the palm of his hand with his own saliva and carried on from where John left off, pumping him fast. John rode the sensation helplessly until he came over Sherlock's fingers and his own belly. He was still gasping, mouth open and eyes closed, when he felt Sherlock licking him clean. John let out a whimper and felt his cock twitch with an aftershock at Sherlock's open wantonness, this newfound brazen display of his sexuality. John had only ever known Sherlock to hum a quiet tone of approval when he swallowed down what John gave him.

Sherlock bent over to rub his lips against John's cheekbones, and Christ, John could _smell_ himself.

"That was," Sherlock said in a low voice, "good. Yes, very...good."

In response, John rubbed his fingers over Sherlock's spine and he arched like a cat.

"I have been thinking, John..."

"Oh, dear. That's never a good thing."

"Shut up. I've been thinking about what you suggested."

John wracked his brain for a few moments, but Sherlock finally gave up waiting and poked him in the side.

"The...licking. That you talked about. I want that."

The corners of John's eyes crinkled when they met Sherlock's and he laid a tender, lingering kiss on his lips.

"I'll look forward to it," he replied.

* * *

Several days later, steam poured forth into their bedroom as Sherlock strode out of the bathroom, naked and semi-erect. Maybe, thought Sherlock, John was onto something with his whole "preparation leading to anticipation" thing. As Sherlock had lingered in the shower, he had reminisced about their first time, about the way John had guided his tentative explorations of his mouth. John had encouraged Sherlock's aimless kisses and demonstrated his own technique until Sherlock could turn it back around to drive him breathless. Giving even while taking, thought Sherlock, was one of John H. Watson's most impressive talents.

John was stretched out on their bed, a book cradled in his hands in a casual pose that fooled neither of them. Sherlock counted four of John's tells, not the least of which was the sucking in of that lower lip. His eyes darkened as he took in Sherlock from head to toe, slowly placing the book on the nightstand and pulling the blankets away from his body. He held out a single hand to Sherlock, who took it and allowed himself to be pulled onto the bed. John flipped him onto his back and stroked slowly over his chest with both palms. Sherlock kept his face impassive and willed himself not to arch into the touch, to not give away how much he was already knotted up with anticipation.

But John could be quite perceptive at times and his mouth quirked upward on one side. It was a smile reminiscent of the dark smirk that crept out when he was ready to beat someone bloody. But this was a version that only Sherlock ever saw now, a sweet twin of his danger grin, promising only sensual pleasure. It triggered a Pavlovian response in Sherlock, who spread his legs without being aware that he was doing so. John grabbed his wrists and pressed them above his head, and Sherlock bucked and groaned, seeking friction but finding none.

"Something you want?" John asked with a chuckle. He darted to place his lips against Sherlock's ear, exhaling a hot breath over it. "I'll give you anything, absolutely everything," John whispered. Sherlock jerked his hands out of John's grip and seized him by the back of his neck, kissing him greedily, sucking his tongue, nibbling at his lower lip. In between kisses, John managed to murmur a steady stream of filth at him.

"Want you, Sherlock. Can I? Please say yes, tell me I can. Tell me I can eat you out, love, I want it. Say yes," John pleaded, rubbing his cock against Sherlock's hip. Sherlock gripped his arse and kneaded, trying to find the words. He pushed John a short distance from him and mouthed against his sensitive neck, sucking a bit of skin between his teeth and nipping the way he knew John loved. John cried out and arced away from Sherlock, gripping his bicep. He was breathing hard now but he rallied, tugging Sherlock's hand over to his mouth. John wriggled his tongue at the base of his fingers where they met his palm and Sherlock let out an involuntary gasp.

"Let me?" John asked, his mouth still pressed against Sherlock's palm. "I'll take care of you, make sure you love it," John said. His eyes were hooded with lust and Sherlock felt his length pulse against him. Sherlock nodded, refraining from speaking lest his "yes" come out as a squeak. John smiled and then licked Sherlock's middle and pointer fingers apart.

John guided Sherlock over onto his knees, rubbing gentle hands over his back. This was comfortable territory, at least; being taken from behind led to excellent prostate stimulation for Sherlock and delightfully candid noises from John. But now Sherlock's treacherous body betrayed his anxiety. His thighs were trembling with nerves and his elbows were locked, hoisting him awkwardly up in place.

"Baby," John said, rubbing one hand soothingly over his arse. Sherlock blinked. John had only ever called him that once. It was when he'd lain stunned in an alleyway, listening to the sounds of an ambulance and wondering why they were growing louder in his ears. He'd been concussed, hadn't been able to focus, but he'd smiled up at John's words, at his audacity in calling him by such a diminutive.

"Relax, baby," John said, pressing his forehead against Sherlock's thigh. "I love you," he murmured, and Sherlock's breathing slowed in response. He trusted John. John had never recoiled from his body, had begged him for this.

"Do you still...?" John asked. Sherlock breathed deeply for the space of about ten seconds and said, "Yes, John. Please." With that reply, he felt as though his strings had been cut, and he melted into John's touch. His heart was thudding in his ears as John guided his head and shoulders onto the bed. John turned his face to the side for him on his elbows and smoothed his hair out of the way, kissing his cheek. As John pulled away and down he made sure that his body never distanced itself too far from Sherlock's, made sure that Sherlock could still feel his warmth. Sherlock relaxed further when he felt John massaging his thighs, rubbing his thumbs up the center. This was good, familiar. John dug all his fingers into Sherlock's buttocks, kneading the muscles until they gave up the fight. Sherlock heard John's breathing grow heavier when he parted him, heard his breath catch as he stared.

"God, you've no idea," John whispered. "So perfect," he said. To Sherlock's surprise, he released him and pressed his face to Sherlock's lower back. Sherlock started at the feel of John's breath, and when exactly had he become so sensitive there?

It was when John let his tongue out to lave over his tailbone that Sherlock began to let go of all his inhibitions entirely.

Sherlock let out a strangled noise, jerking into John's touch. Things devolved very quickly after that, and Sherlock soon found himself on the losing side of John's campaign against his rationality. John worked his way lower, spreading Sherlock's cheeks again as he went. He painted broad strokes from top to bottom, pressing firmly against Sherlock's perineum with the flat of his tongue. Somewhere, Sherlock thought, someone was letting loose with an absolute stream of embarrassing and obscene noises.

 _Tingling, warm, wet_ , were some of the words that floated across Sherlock's consciousness. He was aware of his cock, heavy between his legs, jerking upwards at intervals as John’s mouth worked against him. Sherlock tried, then failed to parse the sensations.

Circling, there was that. Oh, god, the circling of his hole with what had to be the tip of John's tongue. Sherlock whined at the thought. Then a hot, wet sweep against him, then another one, covering the entirety of his entrance and beyond. This wasn't sexual, it was fucking magical, thought Sherlock. Lips were brought into play, impossibly, kissing at him, and Sherlock moaned as he felt what could only be the sides of his rim being sucked at. John returned to the circling, very slowly, and Sherlock felt that he was very slowly being driven out of his mind. He canted his arse upwards and suspected that the words, "please, fucking hell, please John, more," were streaming out of his mouth like a pornographic salutation to the gods.

No, this couldn't be happening. That tight ring of muscle surely wasn't meant to be so pampered, so luxuriously spoiled with such languor-inducing caresses and the most beseeching of smooth, wet nudges. This wasn't like being massaged by John's short, nimble fingers at all, which Sherlock loved to welcome and admit. No, this was so filthy it almost couldn't be borne, and Sherlock shouted in shock as he felt himself open for John's tongue. John backed away from him to mutter, "yeah, Sherlock, oh, yeah," and then he spread him once again with his thumbs. No finger ever felt so slick, so dirty, so good, and John pushed in mercilessly and tongue-fucked him. Sherlock wasn't sure he could speak now or ever again. All of him was soft and utterly open to John, all of him except his prick and that was so very hard. Sherlock wanted to grab himself, it wouldn't take but a moment and he needed to touch himself so much, and he was thinking about how good it would be to come with John's tongue in him, how perfect it would feel for his cock to swell and for him to contract around John's tongue how perfect it would feel how perfect John it would how John

how

John

perfect

John

John

Johnnnn

Maybe thirty seconds passed.

Maybe thirty years.

Sherlock didn't remember exactly how much time had gone by from the moment of his climax until he came back to full cognizance. But he never forgot the noise John made when he froze behind him and came all over his arse, marking him with the evidence of his desire.

* * *

Sherlock was still staring off into space, breathing shallowly on his side where John had rolled him. John had been concerned by his lack of responsiveness at first but felt much better once his lover had feebly fumbled for his fingers.

After a time, Sherlock cleared his throat. “Well,” he rasped.

John grinned at no one in particular. "How are we feeling about that?" he asked him kindly.

"It was. It...yes. I loved it."

Without warning, Sherlock seized John's chin and kissed him, pushing his tongue deep into his mouth. He withdrew and purred, " _I fucking loved it_ ," before laying a sweet peck on John's nose.

"Um," croaked John, now knocked quite a bit off kilter. "I was happy to oblige," he said. Sherlock snuggled up against him, but the thoughtful silence surrounding them let John know the discussion wasn't quite over.

"I could certainly see repeating that," said Sherlock. John let out a hum of affirmation, pleased. "Maybe with a few changes, next time?" suggested Sherlock.

"Anything you want, love," John murmured sleepily as Sherlock petted his hair.

"I was wondering, for instance, whether you would prefer for me to rim you in your chair or on the sofa?" Sherlock asked.

**END**

**Author's Note:**

> Come on, John, even I know the answer to this one.
> 
> It'll be both. Obviously.


End file.
